Microstructure and electrochemical performances of LiF-coated spinel LiMn_2O_4  

作　　者：白莹 吴川 吴锋 

机构地区：[1]School of Chemical Engineering and Environment,Beijing Institute of Technology [2]National Development Center for High Technology Green Materials,Beijing 100081,China

出　　处：《中国有色金属学会会刊：英文版》2007年第A02期892-896,共5页Transactions of Nonferrous Metals Society of China

基　　金：Project (2002CB211800) supported by the National Basic Research Program of China;project (000Y05-21) supported by the Excellent Young Scholar Research Fund of Beijing Institute of Technology;project (20060542012) supported by the Teaching and Research Fund of Beijing Institute of Technology

摘　　要：LiF-coated LiMn2O4 samples were prepared via a chemical method. X-ray diffraction(XRD) patterns show that the bare LiMn2O4 and the LiF-coated LiMn2O4 samples are all spinel structure in Fd 3mspace group. The apparent morphologies,the spectroscopic properties and the LiF distributions of the as-prepared samples were studied by scanning electronic microscopy(SEM),Fourier infrared spectroscopy(FTIR),transmission electronic microscopy(TEM),selected area electron diffractometry(SAED) respectively. The LiF-coated LiMn2O4 gets a more stable surface than bare LiMn2O4,and changes the interaction between the cathode material and the electrolyte. Therefore,it can endure overcharge in the secondary lithium batteries,and achieve better electrochemical performances even when charged to 4.7 V and 4.9 V.LiF-coated LiMn2O4 samples were prepared via a chemical method. X-ray diffraction （XRD） patterns show that the bare LiMn2O4 and the LiF-coated LiMn2O4 samples are all spinel structure in Fd3m space group. The apparent morphologies, the spectroscopic properties and the LiF distributions of the as-prepared samples were studied by scanning electronic microscopy （SEM）, Fourier infrared spectroscopy （FTIR）, transmission electronic microscopy （TEM）, selected area electron diffractometry （SAED） respectively. The LiF-coated LiMn2O4 gets a more stable surface than bare LiMn2O4, and changes the interaction between the cathode material and the electrolyte. Therefore, it can endure overcharge in the secondary lithium batteries, and achieve better electrochemical performances even when charged to 4.7 V and 4.9 V.

关 键 词：尖晶石型锰酸锂 锂离子电池 表面修饰 氟化锂涂层 

分 类 号：TG115[金属学及工艺—物理冶金]